Organic hydroperoxide resistance (Ohr) enzymes are highly efficient Cys-based peroxidases that play central roles in bacterial response to fatty acid hydroperoxides and peroxynitrite, two oxidants that are generated during host-pathogen interactions. In the active site of Ohr proteins, the conserved Arg (Arg19 in Ohr from Xylella fastidiosa) and Glu (Glu51 in Ohr from Xylella fastidiosa) residues, among other factors, are involved in the extremely high reactivity of the peroxidatic Cys (Cp) toward hydroperoxides...

Although it has been recognized that intestinal bacteria play an important role in the pathology of human ulcerative colitis (UC), specific pathogenic bacteria for UC have not been identified. We investigated the influence of Paraclostridium bifermentans PAGU1678 strain on the pathology of a UC mouse model and found it increased UC pathosis scores such as loose and bloody stools, reduced diversity of fecal flora, disappearance of the crypt structure of distal colon tissue, destruction of intestinal epithelial cells, and atrophy of the colon...

Subclinical gut inflammation occurring in patients affected by spondyloarthritis (SpA) is correlated with the severity of spine inflammation. Several evidences indicate that dysbiosis occurs in SpA, and that may modulate intestinal permeability and intestinal immune responses. The presence of intestinal dysbiosis is accompanied in SpA patients with the presence of zonulin-dependent alterations of gut-epithelial and gut-vascular barriers. The leakage of epithelial and endothelial surface layers is followed by the translocation of bacterial products, such as lipopolysaccharide and intestinal fatty acid binding protein, in the systemic circulation...

The cecum plays an important role in the feed fermentation of ruminants. However, information is very limited regarding the cecal microbiota and their methane production. In the present study, the cecal content from twelve local Chinese goats, fed with either a hay diet (0% grain) or a high-grain diet (71.5% grain), were used to investigate the bacterial and archaeal community and their methanogenic potential. Microbial community analysis was determined using high-throughput sequencing of 16S rRNA genes and real-time PCR, and the methanogenesis potential was assessed by in vitro fermentation with ground corn or hay as substrates...

Serine hydrolases play diverse roles in regulating host-pathogen interactions in a number of organisms, yet few have been characterized in the human pathogen Staphylococcus aureus. Here we describe a chemical proteomic screen that identified ten previously uncharacterized S. aureus serine hydrolases that mostly lack human homologs. We termed these enzymes fluorophosphonate-binding hydrolases (FphA-J). One hydrolase, FphB, can process short fatty acid esters, exhibits increased activity in response to host cell factors, is located predominantly on the bacterial cell surface in a subset of cells, and is concentrated in the division septum...

This study evaluated the effects of increasing concentrations of spray-dried yeast cell wall (YCW) in diets for healthy adult cats on apparent nutrient digestibility and on bacterial composition and fermentation products in the stool. Fourteen cats with an average weight of 4.40 ± 1.05 kg and an average age of 6.2 ± 0.54 years were used and assigned to treatments in an unbalanced randomized block design (by experimental period) with two blocks and three or four cats per diet in each block. Treatments included: control (0% YCW), 0...

A Gram-stain-negative, aerobic, non-motile, and carrageenan-degrading bacterial strain, designated OISW-17T , was isolated from seawater around Oido, an island of South Korea, and its taxonomic position was determined using a polyphasic study. Optimal growth of the novel strain occurred at 20-25 °C and in the presence of 2.0% (w/v) NaCl. Phylogenetic trees using 16S rRNA gene sequences showed that strain OISW-17T forms a cluster with the type strains of Dokdonia species. The novel strain exhibited 16S rRNA gene sequence similarities of 95...

Marginal sea sediments receive organic substrates of different origins, but whether and to what extent sediment microbial communities are reflective of the different sources of organic substrates remain unclear. To address these questions, sediment samples were collected in two connected China marginal seas, i.e., Bohai Sea and Yellow Sea, and their two major tributaries (Yellow River and Liao River). Sediment bacterial community composition (BCC) was examined using 16S rRNA gene pyrosequencing. In addition, physicochemical variables that describe environmental conditions and sediment features were measured...

Background: Dysfunction of the gut microbiota is frequently reported as a manifestation of chronic diseases, and therefore presents as a modifiable risk factor in their development. Diet is a major regulator of the gut microbiota and certain types of dietary fiber may modify bacterial numbers and metabolism, including short-chain fatty acid (SCFA) generation. Objective: A systematic review and meta-analysis were undertaken to assess the effect of dietary fiber interventions on gut microbiota composition in healthy adults...

Background: Livestock production should respond to societal, environmental and economic changes. Since 2006 and the ban on antibiotics as growth factors in European Union, the use of probiotics has become widespread and has demonstrated the effect of intestinal microbiota on the performance of farm animals. Objective: The aim of this study was to investigate the effect of supplementation with Lactobacillus salivarius (as a probiotics strain or combined with other strains) on zootechnical performance, metabolic and immune gene expression and intestinal microbiota diversity in mule ducks using high-throughput sequencing and real-time PCR...

Lipocalin 2 (LCN2) is a highly conserved secreted adipokine acting as a serum transport protein for small hydrophobic molecules such as fatty acids and steroids. In addition, LCN2 limits bacterial growth by sequestering iron-containing siderophores and further protects against intestinal inflammation and tumorigenesis associated with alterations in the microbiota. Human LCN2 contains one N -glycosylation site conserved in other species. It was postulated that this post-translational modification could facilitate protein folding, protects from proteolysis, is required for proper trafficking from the Golgi apparatus to the cell surface, and might be relevant for effective secretion...

Microalgae-based treatment systems have been successfully used for the polishing of domestic wastewater. Research is underway in studying the suitability of using these systems as main treatment units. This study focuses on comparing the performances of a mixed microalgal culture and an aerobic bacterial culture, based on the kinetic evaluation, in removing organic carbon from a kitchen wastewater. The two systems were operated at six different solid retention times (SRTs)-2, 4, 6, 8, 10, and 12 days in continuous mode...

Acinetobacter guillouiae SFC 500-1A is an environmental bacterium able to efficiently co-remediate phenol and Cr(VI). To further understand the molecular mechanisms triggered in this strain during the bioremediation process, variations in the proteomic profile after treatment with phenol and phenol plus Cr(VI) were evaluated. The proteomic analysis revealed the induction of the β-ketoadipate pathway for phenol oxidation and the assimilation of degradation products through TCA cycle and glyoxylate shunt. Phenol exposure increased the abundance of proteins associated to energetic processes and ATP synthesis, but it also triggered cellular stress...

Bacterial non-coding RNAs (ncRNAs) are widely studied and found to play important roles in regulating various cellular processes. Recently, many ncRNAs have been discovered to be transcribed or processed from 3' untranslated regions (3' UTRs). Here we reported a novel 3' UTR-derived ncRNA, RibS, which could influence biofilm formation of Salmonella enterica serovar Typhi (S. Typhi). RibS was confirmed to be a ∼700 nt processed product produced by RNase III-catalyzed cleavage from the 3' UTR of riboflavin synthase subunit alpha mRNA, RibE...

A Gram-stain-positive, rod-shaped, slightly halotolerant, nitrate-reducing bacterial strain, designated ET03T , was isolated from the cast of an earthworm (Eisenia fetida) reared at the Centre of Floriculture and Agribusiness Management, University of North Bengal at Siliguri, West Bengal, India. On the basis of 16S rRNA gene sequence phylogeny, the closest relative of strain ET03T was Chryseomicrobium palamuruense PU1T (99.1 % similarity). The DNA G+C content of strain ET03T was 42.9 mol%. Strain ET03T contained menaquinone-8 as the most predominant menaquinone and phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and phosphatidylglycerol as the main polar lipids...

Irritable bowel syndrome (IBS), a common functional gastrointestinal disorder, is classified according to bowel habits as IBS with constipation (IBS-C), with diarrhea (IBS-D), with alternating constipation and diarrhea (IBS-M), and unsubtyped (IBS-U). The mechanisms leading to the different IBS forms are mostly unknown. This study aims to evaluate whether specific fecal bacterial taxa and/or short-chain fatty acids (SCFAs) can be used to distinguish IBS subtypes and are relevant for explaining the clinical differences between IBS sub-categories...

Dietary resistant starch (RS) may have prebiotic properties but its effects on fermentation and the microbial population are inconsistent. This meta-analysis aimed to quantify the relationship between RS type 2 (RS2) and intestinal short-chain fatty acids (SCFA) and pH as well as certain key bacterial taxa for intestinal health in pigs. From the 24 included articles with sufficient information about the animal, and dietary and physiological measurements published between 2000 and 2017, individual sub-data sets for fermentation metabolites, pH, bacterial abundances and apparent total tract digestibility were built and used to parameterize prediction models on the effect of RS2, accounting for inter- and intra-study variability...

Strain Marseille-P2341T , a nonmotile, nonspore-forming, Gram-stain-positive anaerobic coccus, was isolated in the vaginal specimen of a patient with bacterial vaginosis using culturomics. Its growth occurred at temperatures ranging from 25 to 42°C, with pH between 6.5 and 8.5, and at NaCl concentrations lower than 5%. The major fatty acids were C18:1n9 (27.7%) and C16:0 (24.4%). Its genome is 1,671,491 bp long with 49.48 mol% of G+C content. It is composed of 1,501 genes: 1,446 were protein-coding genes and 55 were RNAs...